WO1991005860A1 - Particules non infectieuses de vih-1 et leurs emplois - Google Patents

Particules non infectieuses de vih-1 et leurs emplois Download PDF

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WO1991005860A1
WO1991005860A1 PCT/US1990/005932 US9005932W WO9105860A1 WO 1991005860 A1 WO1991005860 A1 WO 1991005860A1 US 9005932 W US9005932 W US 9005932W WO 9105860 A1 WO9105860 A1 WO 9105860A1
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hiv
dna
wild
mutant
type
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Richard A. Young
David Baltimore
Anna Aldovini
Didier Trono
Mark B. Feinberg
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Whitehead Institute For Biomedical Research
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    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12NMICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N7/00Viruses; Bacteriophages; Compositions thereof; Preparation or purification thereof
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61KPREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K39/00Medicinal preparations containing antigens or antibodies
    • A61K39/12Viral antigens
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61KPREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K39/00Medicinal preparations containing antigens or antibodies
    • A61K39/12Viral antigens
    • A61K39/21Retroviridae, e.g. equine infectious anemia virus
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61PSPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P31/00Antiinfectives, i.e. antibiotics, antiseptics, chemotherapeutics
    • A61P31/12Antivirals
    • AHUMAN NECESSITIES
    • A61MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61KPREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K39/00Medicinal preparations containing antigens or antibodies
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    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
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    • C12N2740/00Reverse transcribing RNA viruses
    • C12N2740/00011Details
    • C12N2740/10011Retroviridae
    • C12N2740/16011Human Immunodeficiency Virus, HIV
    • C12N2740/16021Viruses as such, e.g. new isolates, mutants or their genomic sequences
    • CCHEMISTRY; METALLURGY
    • C12BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12NMICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N2740/00Reverse transcribing RNA viruses
    • C12N2740/00011Details
    • C12N2740/10011Retroviridae
    • C12N2740/16011Human Immunodeficiency Virus, HIV
    • C12N2740/16034Use of virus or viral component as vaccine, e.g. live-attenuated or inactivated virus, VLP, viral protein

Definitions

  • HIV-1 Human immunodeficiency virus type 1
  • AIDS acquired immune deficiency syndrome
  • DPA D -penicillamine
  • anti- sense oligonucleotide inhibitors designed specifically to interfere with HIV
  • the present invention relates to HIV-1 mutant constructs which include a mutation in a nucleotide sequence critical in packaging HIV-1 and which, when expressed in susceptible mammalian cells, produce non-infectious viral particles, as well as to HIV-1 mutant expression products.
  • HIV-1 particles which do not contain the viral genome have been made.
  • Such mutant HIV-1 particles provide a means to produce vaccines which are based on intact, fully immunogenic, but non-infectious virus particles.
  • Such vaccines can be used to induce an anti-HIV-1 response in an individual, either prior to or after infection with HIV-1, resulting in enhanced resistance by the individual to the virus.
  • the invention further relates to vaccines which contain a HIV-1 mutant expression product and to methods of immunizing an individual by administration of the vaccine.
  • the present invention relates to HIV-1 packaging mutations which differ from wild- type HIV-1 in that they include at least one alteration (a deletion, insertion or substitution) in the nucleotide sequence of the corresponding region of the wild-type DNA critical for viral packaging or in the amino acid sequence of the corresponding region of the wild-type product critical for viral
  • HIV-1 gag sequences such as in p7 gag (alternatively referred to as p15 ga g )
  • sequences between the first HIV-1 splice donor site and the gag initiation codon which are sequences homologous to the defined ⁇ sites of other viruses, have been shown to result in blocking of packaging of viral RNA and in production of
  • HIV-1 genome now identified as the HIV-1 ⁇ site and, similarly, have been shown to produce non- infectious viral particles whose protein content is the same as that of the wild- type virus.
  • Figure 1 is a partial HIV-1 nucleotide sequence (nucleotides 1351-1980) and the deduced amino acid sequence for that partial sequence, (Ratner, L. et al., Nature, 313:277-284 (1985)), on which the location of the mutations in HIV-1 gag described herein are indicated.
  • Figure 2 is a schematic representation of HIV-1 mutations.
  • Figure 2A location and size of deletions affecting the HIV-1 ⁇ site.
  • Figure 2B amino acid changes in the metal binding motifs of HIV-1 gag produced by various point mutations. The guanine nucleotide in the second position of codons coding for cysteine (C) residues was changed to an adenosine residue, producing codons coding for tyrosine (Y).
  • Figure 3 shows results of assessment of transcription and translation of HIV-1 mutants in cos-1 cells.
  • Figure 3A shows results of Northern Blot analysis showing a comparison of viral transcripts in RNA extracted from cos-1 cells transfected with wild-type or mutant HIV-1 genomes.
  • Figure 3B shows the results of SDS-PAGE analyses of HIV-1 specific proteins in transfected cos-1 cells.
  • FIG. 4 shows results of analysis of HIV-1 mutant particles by Western Blot.
  • Figure 5 shows results of assessment of the nucleic acid content of viral particles present in the supernatant from transfected Cos-1 cells.
  • Figure 6A is a schematic representation of the replication defective HIV-1 virus p ⁇ PAC-Hygro, in which there are the following alterations from wild type HIV-1: a deletion in the ⁇ site; alteration of the guanine nucleotide in the second position of codons coding for cysteine (C) residues to an adenosine residue, producing codons coding for tyrosine (Y); and replacement the nef gene with the hygromycine resistance gene.
  • Figure 7 is a schematic representation of the gag-coding region of HIV-1 with nucleotide numbers indicating the initiation codon, the cleavage sites between p17, p24 and p15, and the gag termination codon. The nucleotide differences between wild type and bCA20 are indicated. Below is shown the amino acid sequence of the two HIV-1 Cys-His boxes, and of the intervening sequence, where the bCA20 mutation was introduced. Figure 8 shows the result of immunoblot
  • Figure 9 shows results of study of viral RNA hybridization by slot-blot analysis of the supernatant from HT4( ⁇ E-dhfr) cells.
  • HT4(R7-dhfr), HT4 (WT- ⁇ E-dhfr) and HT4 (bCA20- ⁇ E-dhfr) by electron microscopy.
  • the present invention is based on results of an investigation of the RNA and the protein sequences involved in HIV-1 packaging. Assessment of the effect of various point deletion or insertion mutations has shown the critical nature of the HIV-1 gag region in packaging genomic RNA into the virus particle and has demonstrated the occurrence and location of a HIV-1 RNA packaging ( ⁇ ) site, which is also critical to packaging of the virus.
  • point mutations that alter cysteine residues in one or both metal binding motifs of p7, a cleavage product of the gag precursor; insertion mutations in pl5 which change the length and the nature of the intervening sequences between the two
  • HIV-1 RNA sequences now shown to be essential for packaging of the virus have been made and, for both types of HIV-1 mutants, HIV-1 RNA packaging has been shown to be inefficient.
  • two types of HIV-1 mutants have been made and shown to be defective in their ability to package the viral RNA: 1) HIV-1 mutants in which there are alterations or mutations in gag coding sequences and 2) HIV-1 mutants in which there are alterations or mutations in
  • HIV-1 gag mutants sequences in the HIV-1 genome which are homologous to the sequences of the defined ⁇ sites of other viruses.
  • the two types of HIV-1 mutants produced are referred to, respectively, as HIV-1 gag mutants and HIV-1 ⁇ mutants.
  • mutations in the form of substitutions of selected nucleotides which in wild-type HIV-1 encode cysteine residues, to result in a nucleotide sequence which encodes tyrosine in the corresponding location have been introduced into the nucleotide sequences that encode the HIV-1 gag metal binding motifs.
  • This type of HIV-1 gag mutant is referred to as a HIV-1 gag metal binding motif mutant.
  • HIV-1 gag insertion mutant In a second type of HIV-1 gag mutant (referred to as a HIV-1 gag insertion mutant), a nucleotide insertion which results in alteration in the nature and the length of the intervening sequence between the two HIV-1 gag Cys-His boxes has been made.
  • Three deposits have been made 10/13/89 and 10/16/89 at the American Type Culture Collection, Rockville, MD, in support of the subject application: a HIV-1 gag metal binding motif mutant, designated pA14-15HXB (ATCC Accession #68123); an HIV-1 gag insertion mutant designated Plasmid bCA20-dhfr (ATCC Accession #40682); and a HIV-1 ⁇ mutant, designated pA3HXB (ATCC Accession #68122). These deposits have been made under the terms of the Budapest Treaty and, upon grant of a U.S. patent, all restrictions on their availability will be irrevocably removed.
  • gag and the ⁇ types of mutations were introduced into appropriate cells, in which they were expressed.
  • HIV-1 gag metal binding motif mutants or the ⁇ mutants have been shown to be normal in protein .content (i.e., not substantially different in protein content from that of the wild type HIV-1), to be missing genomic RNA and to be noninfectious.
  • the alteration in the HIV-1 gag insertion mutant has been shown to be lethal for viral replication and the viral particles generated have been shown to be noninfectious.
  • Such viral products which are essentially the same in protein content as wild type HIV-1, but are not infectious, can be used as an anti-HIV-1 vaccine.
  • HIV-1 mutant constructs constructed of HIV-1 mutants, whose expression in host cells results in production of noninfectious HIV-1 mutants (referred to as mutant HIV-1 particles); and the use of the HIV-1 mutant particles or HIV-1 mutant expression
  • Nucleotide locations referred to are those indicated by Ratner and co-workers; the relevant portion of the HIV-1 genome is represented in Figure 1. Ratner, L. et al., Nature 313:277-284 (1985). Assessment of HIV-1 Packaging Sequences and
  • Unspliced genomic RNA is an indispensable component of the viral particle and the retrovirus packaging process can discriminate between unspliced viral RNA and spliced viral or cellular mRNAs. This discrimination is very likely the result of interaction between specific viral RNA sequences and viral proteins. Varmus, H., Science 216: 812-820 (1982); and Weiss et al. , RNA Tumor Virus, Cold Spring
  • RNA sequences essential for packaging have been mapped to a site near the 5' end of the viral genome.
  • deletion mutations were constructed in homologous sequences in the HIV-1 genome to investigate whether this region acts as a packaging signal for the human virus.
  • two deletion mutations were constructed: one in which nucleotides 293-331, inclusive, were deleted, to create the mutant pA3-HXB and one in which nucleotides 293-313, inclusive, were deleted, to produce pA4-HXB ( Figure 2A).
  • deletions occur between the first splice donor site and the gag initiation codon, leaving the consensus sequence for the first splice donor site intact.
  • Other deletions in the HIV-1 ⁇ site can also be made.
  • Those shown (e.g., by the methods described herein) to be packaging defective mutants can be used, for examples as an anti-HIV vaccine, as is described for the pA3-HXB and pA4-HXB mutants. Construction of HIV-1 gag Mutants
  • One or more proteins encoded by sequences at the 3' end of the gag gene are thought to be involved in the recognition of viral RNA, as deletion mutations at this locus appear to produce particles lacking viral RNA. Henderson, L.E. et al., J. Biol. Chem., 256:8400-8406 (1981); Oroszlan, S. and T.D.
  • CysX 2 CysX 3 GlyHisX 4 Cys is a common feature of the carboxyl terminus of the gag precursor in all retroviruses. Berg, J., Science 232:485-486 (1986). This motif occurs once in the murine retroviruses, and twice in most other retroviruses studied thus far.
  • gag zinc fingers are necessary for the correct positioning of the tRNA primer on the replication initiation site at the 5' end of the RNA genome. Prats, A.C. et al., J .EMBO 7:1777- 1783 (1988).
  • oligo-mediated mutagenesis was employed to substitute tyrosines for the first two cysteines of the second metal binding motif, producing the mutant pA15-HXB ( Figure 2B and Example 1).
  • substitution of an amino acid other than tyrosine for some or all of these cysteine residues can be made, using the procedures described herein.
  • gag gene of retroviruses encodes proteins that are critical to viral assembly and release, stabilization of the virion, uncoating of the viral RNA, initiation of reverse transcription and perhaps integration.
  • HIV-1 expresses its gag gene as a polypeptide precursor, Pr55 gag . This precursor is subsequently phosphorylated and
  • HIV-1 p15 ga g is a 123 amino-acid long protein, encoded by the 3' end of the gag gene. It carries striking similarities with retroviral nucleocapsid proteins (NC). These similarities include, in the p9 region, two tandem copies, separated by 7 amino acids, of a conserved motif of three cysteine residues and one histidine residue, referred to as the Cys-His box (see Figures 1 and 7). Covy, S.N., Nucleic Acids Res.14:137-145) In this motif, if the N terminus-proximal cysteine is designated n, the two other cysteine residues are located at n+3 and n+13, whereas the histidine residue is at n+8.
  • NC retroviral nucleocapsid proteins
  • myeloblastosis virus (AMV) p12 gag binds 6 5 Zn(II) in a zinc blotting technique (Schiff, L.A., et al., Proc. Natl. Acad. Sci. USA 83:7246-7250 (1988).
  • NC is tightly associated with the genomic RNA and that purified NC binds nucleic acids in vitro, although in a non-specific manner (Davis, J.M., et al., J. Virol. 18:709-718 (1976); Nissen-Meyer, J. and A.K. Abraham, J. Mol. Biol. 142:19-28 (1980)).
  • M-MuLV Moloney leukemia virus
  • RSV Rous sarcoma virus
  • the plasmid W13 which contains an infectious copy of the HIV-HXB2-D proviral DNA, was modified by the insertion of an 8 nucleotide-long Cla I linker.
  • the linker was inserted in a unique Apa I site present at position 2009 and the Cla I site was then blunted with Klenow in order to rectify the gag reading frame.
  • the two residues which follow the first Cys-His box (arginine- alanine) in
  • pA3-HXB in which nucleotides 293 to 331, as they occur in wild type HIV-1 are deleted
  • pA4-HXB in which nucleotides 293-313, as they occur in wild type HIV-1, are deleted
  • pA15-HXB in which the first two cysteines of the second metal binding motif of p7 are replaced by tyrosines
  • pA14-15HXB in which the first two cysteines of both of the metal binding motifs of p7 are replaced by tyrosines.
  • An additional mutant, designated p ⁇ PAC-Hygro has also been constructed.
  • p ⁇ PAC-Hygro includes the 39 bp
  • the cos-1 cells were examined for evidence of viral gene expression.
  • the SV40 - transformed African Green Monkey kidney cell line cos-1 (Gluzman, Y., Cell, 23:175-182 (1981)) was obtained from G. Khoury (NIH) and maintained in DME media supplemented with 10% fetal bovine serum.
  • Northern Blot analysis comparing viral transcripts in RNA extracted from cos-1 cells transfected with wild-type or mutant HIV-1 genomes was carried out, using a HIV-1 specific probe which was a 32 P random primed full length viral DNA. 15/xg of total celluar
  • RNA transcripts in cells transfected with the mutant plasmids are indistinguishable from that obtained from cells transfected with the wild-type plasmid.
  • all three classes of HIV-1 mRNA are present: the 9.2 genomic mRNA, a 4.3 kd spliced mRNA encoding the env and the vif genes, and the heterogeneous
  • HIV-1 structural proteins was investigated by metabolic labeling of transfected cos-1 cells with 35 S methionine, followed by immuno- precipitation of viral proteins using human and monoclonal mouse sera with defined specificity of
  • H9 cells infected with supernatant from cos-1 cells transfected with pHXB2gpt wild type HIV-1
  • both the percentage of HIV-1 antigen positive cells and the reverse transcriptase activity increased with time (Table 1).
  • H9 cultures exposed to supernatants derived from cos-1 cells transfected with mutant viruses were not positive in cellular p24 immunofluorescence, RT activity or particle-associated p24 assays. These assays were negative for at least 30 days after the H9 cells were exposed to mutant viral particles.
  • mutant viral particles from cos-1 cell transfections were studied to determine whether the lack of productive infection of H9 cells could be due to defective virions.
  • Viral particles in the cos-1 supernatants were pelleted by centrifugation and a quantitative analysis of the amounts of p24 present in the pellet was performed using a p24 ELISA. p24 values ranged from 15 to 20ng in each sample (Table 2).
  • a reverse transcriptase assay performed on the pelleted viral particles revealed a two-fold
  • RNA present in these virions was investigated by extracting RNA directly from virions present in the supernatant, immobilizing the nucleic acid on nitrocellulose slot blots and probing with a labelled Clal/EcoRI 3.8 gag-pol fragment. Results are shown in Figure 5. At least a 100-fold reduction in the RNA content was observed for both ⁇ and gag metal binding motif mutants, relative to the wild-type. Thus, for both ⁇ and gag metal binding motif mutants, HIV-1 RNA is not packaged efficiently in the viral particles. The lack of genomic RNA in mutant viral particles reflects a packaging defect, rather than the absence of intracellular genomic RNA, as evidenced by the fact that these transcripts are present in cells transfected with mutant genomes (Figure 3A).
  • Wild type and mutant HIV-1 particle morphology was examined by electron microscopy. Careful scoring of the sections indicated that the majority of the mutant particles are less electron dense than are wild- type viral particles. The appearance of empty mutant virions is consistent with the RNA and protein analysis, which indicate that the mutant virions lack genomic RNA.
  • the Role of HIV-1 ⁇ and Metal Binding Motifs in Viral Packaging was examined by electron microscopy. Careful scoring of the sections indicated that the majority of the mutant particles are less electron dense than are wild- type viral particles. The appearance of empty mutant virions is consistent with the RNA and protein analysis, which indicate that the mutant virions lack genomic RNA.
  • HIV-1 ⁇ site is located in the 5' leader region of the genomic viral RNA and that deletions located immediately 3' to the splice donor site as small as 21 base pairs can produce a defect in packaging.
  • results described here indicate that HIV-1 ⁇ site mutants exhibit normal patterns of gene expression in transfected cells and that the viral particles produced by these mutants, while lacking detectable RNA, appear normal in protein composition.
  • HIV-1 mutant viruses with lesions in the gag metal binding motifs were shown to produce non- infectious viral particles that are similar, if not identical, to those produced by ⁇ de le tion mutants .
  • the fact that HIV - 1 p7 and ⁇ mutants both produce viral particles lacking genomic RNA is consistent with the idea that HIV-1 packaging involves an interaction between p7 and genomic RNA. If p7 interacts with genomic RNA, the metal binding motifs could play a direct role in binding. It is also possible that the gag metal binding motifs interact with other nucleic acids (e.g., the tRNA primer) or with other proteins tht are important for proper RNA packaging.
  • the HIV-1 packaging mutations described can provide a means to produce noninfectious antigenic particles useful for induction of anti-HIV-1 immune responses.
  • a cell line with a stably integrated mutant provirus has been constructed to provide a source of such noninfectious particles.
  • Potential reversion of point mutations in the provirus should be minimized by the simultaneous presence of the ⁇ site deletion and the four gag cysteine mutations present in A14-15HXB.
  • the possibility that a mutant viral genome might occassionally be packaged cannot be eliminated, but fortuitous packaging of an HIV-1 genome may not lead to a productive infection, both because of the packaging defect and because of the role of the gag metal binding motifs in correctly positioning the tRNA primer necessary for reverse transcription.
  • the HIV-1 genome containing packaging mutations can be divided into 2 independent constructs stably integrated in a cell line, and any rescued genome will be highly
  • Example 3 by transfecting cos cells with bCA20 (the mutated construct) and scoring generation of viral particles by measuring p24 antigen produced and reverse transcriptase activity released in the supernatant. As shown in Table 3 (Example 3), bCA20- induced p24 and reverse transcriptase activity were approximately 40% and 30% of the corresponding wild-type activity, respectively. Thus, the
  • the cos cell supernatant was used to infect H9 cells.
  • An indirect immunofluorescence assay using serum from an HIV-infected individual as detection antibody, was carried out to monitor the H9 cells. After three weeks, no positive cells were detected, demonstrating that the viral particles generated following transfection were noninfectious.
  • Example 3 Cells selected on the basis of appropriate resistance were cloned and analyzed by polymerase chain reaction for the presence of the viral integrant. Analyses, described in Example 3, demonstrated that the mutation present in bCA20 did not affect the synthesis, the cleavage or the stability of the gag precursor.
  • HT4(bCA20- ⁇ E-dhfr) cells and HT4(WT- ⁇ E-dhfr) cells which express a wild-type gag sequence (the control cell line). Results showed that the amount of viral RNA in the supernatant from HT4 (bCA20- ⁇ E-dhfr) was dramatically reduced, in comparison with the amount present in control cell line supernatant.
  • HT4(WT- ⁇ E-dhfr) with the morphology of HT4(R7-dhfr), a cell line infected with an Env + , replication competent version of the same virus showed that the two were very similar (See Figure 10, Panel A and Figure 10, Panel B and Example 3).
  • two dramatic differences were seen when particles released from HT4(bCA20- ⁇ E-dhfr) were compared morphologically with those from HT4(R7-dhfr):
  • HIV-1 mutant constructs which contain mutations in nucleotides which are present in wild-t/pe HIV-1 gag sequences have been constructed, as have mutant constructs which contain mutations in
  • HIV-1 RNA shown to be essential for viral packaging HIV-1 ⁇ site
  • HIV-1 mutant constructs which contain both a mutation in HIV-1 gag sequences and a mutation in HIV-1 RNA shown to be essential for viral packaging have been made.
  • the viral particles produced by cells into which the mutant constructs are introduced can be used to provide protection to an individual against HIV-1 infection, as can mutant expression products (e.g., mutant gag products).
  • mutant expression products e.g., mutant gag products
  • a mutant expression product such as a gag mutant, can be introduced into an individual, resulting in an immune response and production of anti-mutant HIV-1 gag antibodies.
  • mutant HIV-1 viral particles produced in cells into which a mutant has been introduced can be used as a vaccine.
  • viral particles which are produced using one (or more) of the mutations are obtained from the cells in which they are produced, combined as needed with additional components (e.g., an appropriate physiological buffer or carrier, an adjuvant) to produce a vaccine composition and administered (e.g., by injection) to an individual, either prior to or after HIV infection.
  • additional components e.g., an appropriate physiological buffer or carrier, an adjuvant
  • the mutant HIV-1 particles, whose protein content is much like that of wild-type HIV-1 induce an immune response similar to that induced by the wild- type virus but, unlike the wild-type virus, do not infect the recipient because they are unable to do so.
  • A3 TGACGCTCTCGCACCCATCTCTCACCAGTCGCCGCCCCTC, deleting nucleotides 293 to 331 (Ratner, L. et al., Nature 313:277-284 (1985));
  • A4 CTCTCTCCTTCTAGCCTCCGCTCACCAGTCGCCGCCCCTC , deleting nucleotides 293 to 313;
  • A14 TGCCCTTCTTTGCCATAATTGAAATACTTAACAATCTTTC, changing guanosine (G) 1508 and 1517 to adenines
  • A15 TGTCCTTCCTTTCGATATTTCCAATAGCCCTTTTTCCTAG, changing G at position 1571 and 1580 to A.
  • the introduction of the mutations was verified by sequencing different M13mpl8 recombinant DNAs using two specific oligomers A5 : CCATCGATCTAATTCTC and A16: GGCCAGATCTTCCCTAA. Ausubel, F.M. et al.,
  • a Bsshll/Ball 1.9 kb DNA fragment from the mutated M13mpl8 recombinant clones was used to transfer all the different mutations to the wild- type plasmid pHXB2gpt.
  • the full length HIV1 mutant clones were designated pA3HXB , pA4HXB , pAl5HXB and pAl4-15HXB, according to the oligonucleotides used in the mutagenesis.
  • the entire region that had been transferred from the M13mpl8 plasmids was sequenced using double stranded DNA sequencing methods
  • Cos-1 cells were seeded at a density of
  • RNA samples were resuspended in water at identical concentrations of tRNA (1 ⁇ g/ml) and 1, 0.3 and 0.1 equivalents of RNA were loaded on nitrocellulose, where 1 equivalent represents the amount of RNA obtained from cos-1 supernatants containing 18 ng of p24.
  • RNA Slot Blot analysis was performed as previously described. Ausubel, F.M. et a l. , CurrentProtocols in Molecular Biology (Green Publishing and
  • cos-1 cells (4x10 6 ) transfected 48 hours earlier with 10 ⁇ g of each plasmid were labelled for 4 hours with 500 ⁇ Ci of 35 S methionine.
  • As anegative control cells were transfected with the plasmid pHXB2Bam p3, which does not produce virus due to a pos t-transcriptional defect.
  • Feinberg, M.B. et al. Cell 46:807 (1986).
  • Cell lysates were prepared and immunoprecipitations were performed as described. Veronese, F.D. et al., Proc. Natl. Acad. Sci. USA 82:5199 (1985).
  • HIV-1 positive human serum used in these experiments had demonstrated reactivity with all known viral structural proteins.
  • Immuno- precipitated proteins were resolved using a 10% SDS-polyacrylamide gel.
  • Cos-1 cells (4x10 6 ) transfected 48 hours earlier with pHXB2gpt; pA3-HXB; pA4-HXB; PA15-HXB; PA14-15-HXB and PHXB2Bam p3 were metabolically labeled with 500 ⁇ Ci of 35 S methionine for 4 hours.
  • the pellet was resuspended in dissociation buffer (0.01 M Tris-HCL pH 7.3, 0.2% Triton X-100, 0.001M EDTA, 0.005M dithiothreitol (DTT), 0.006M KCL) if reverse transcriptase activity was to be measured, or in 0.2% Triton and Laemli buffer if protein analysis was to be performed.
  • dissociation buffer 0.01 M Tris-HCL pH 7.3, 0.2% Triton X-100, 0.001M EDTA, 0.005M dithiothreitol (DTT), 0.006M KCL
  • RIP Western blot analysis and radio- immunoprecipitations followed the procedure of Veronese et al. Veronese, F.D., et al., Proc. Natl. Acad. Sci. USA, 82:5199-5202 (1985).
  • P24 analysis on tissue culture supernatants or on pelleted virus was performed.
  • DuPont P24 ELISA kit was used and 3 different dilutions of each supernatant were analyzed. RT activity was measured after concentrating 3ml of Cos-1 supernatant from transfections of each mutant by centrifugation for 3 hours at 27,000 rpm.
  • Numbers refer to 1ml of supernatant and are the mean of three experiment. Analysis of protein content of wild-type and mutant particles by
  • W13 was modified by inserting an 8-nucleotide-long Cla I linker in a unique Apa I site present at position 2009, and then blunting this Cla I site with Klenow to rectify the gag reading frame.
  • the mutated construct thpreby obtained is called bCA20-W13.
  • the mutation results in the replacement of the two residues which
  • a p24 antigen was measured using an ELISA assay system (DuPont-NEN, Inc., Billerica, MA)
  • bCA20-induced p24 and reverse transcriptase activities were approximately 40% and 30% of wild-type, respectively. This indicated that the mutation present in bCA20 only mildly interfered with the release of viral particles.
  • the COS cell supernatant was then used to infect H9 cells, which were followed by an indirect immunofluorescence assay (Ho, D.D., et al., Science 226:451-453 (1984)), using serum from an HIV- infected individual as detector antibody. After three weeks, no positive cells were seen. This showed that the particles generated following transfection were non- infectious. Therefore, it could be concluded that the bCA20 mutation was lethal for viral replication.
  • a cell line which constitutively expresses an Env version of this mutant was generated. Expression of the HIV gag gene products is sufficient to generate viral particles in the absence of Env.
  • Such cell lines are made as follows: Briefly, HT4-6C cells (a HeLa cell line expressing the CD4 molecule at its surface, a gift from B. Chesebro) Chesebro, B. and K. Wehrly, J. Virol.
  • HT4(bCA20- ⁇ E-dhfr) was similar to that observed in HT4(WT- ⁇ E-dhfr), which expresses a wild-type gag sequence (not shown).
  • p24 antigen and reverse transcriptase activity were also measured in the supernatants of these cell lines; the ratio of activity of bCA20 to wild-type was grossly similar to those observed with the transient transfection of the corresponding W13 viral constructs (Table 3).
  • Western Blot analysis of cytoplasmic proteins was performed as described previously Trono and co-workers (Trono, D., et al., Cell, October 6, 1989), using an
  • gag precursor synthesis, the cleavage or the stability of the gag precursor.
  • [ 32 P] probe generated with T7 polymerase complementary to nucleotides 8475 to 8900 of the HIV-1 genome.
  • the filter was washed in 0.2xSSC three times at 68°C and exposed to X-ray film. Results showed that the amount of viral RNA present in the supernatant from HT4(bCA20- ⁇ E-dhfr) was dramatically reduced, compared to the control cell line, HT4 (WT- ⁇ E-dhfr) ( Figure 9). Therefore, it was concluded that the bCA20 mutation specifically inhibited the packaging of the viral genomic RNA into particles.
  • HIV-1 virions produced by cells transfected with the bCA20 p15 ga g variant provirus bear a notable resemblance to the virus-like part- icles released from Spodoptera gruiperda insect cells infected with a recombinant baculovirus expression vector encoding the p57 gag precursor of the simian immunodeficiency virus, SIV mac

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Abstract

Structures mutantes de VIH-1 comprenant une mutation dans une séquence de nucléotides présente dans le VIH-1 de type sauvage, dans lesquelles elle est critique dans l'encapsulation du VIH-1, ainsi que des produits d'expression mutants du VIH-1 et des particules virales mutantes du VIH, lesquelles sont non infectieuses. L'invention concerne également des vaccins qui sont des structures mutantes de VIH-1 ou des produits d'expression mutants du VIH-1, ainsi qu'un procédé d'immunisation d'un individu consistant à administrer le vaccin en une dose appropriée.
PCT/US1990/005932 1989-10-16 1990-10-16 Particules non infectieuses de vih-1 et leurs emplois WO1991005860A1 (fr)

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WO1991019803A1 (fr) * 1990-06-19 1991-12-26 Applied Biotechnology, Incorporated Particules virales autoassemblees defectueuses qui ne se propagent pas d'elles-memes
EP0500791A1 (fr) * 1989-10-31 1992-09-02 THE UNITED STATES OF AMERICA as represented by the Secretary UNITED STATES DEPARTMENT OF COMMERCE Conception et construction des mutants retroviraux humains et non infectieux deficients dans l'arn genomique
EP0502105A1 (fr) * 1989-11-20 1992-09-09 Oncogen Limited Partnership Particules retrovirales non replicantes produites par recombinaton employees comme agents antiviraux et immunogenes
WO1992022577A1 (fr) * 1991-06-17 1992-12-23 Neovacs Composes immunogenes a effet notamment anti-cytokine, procede de preparation, compositions pharmaceutiques et kits les renfermant
WO1996005292A1 (fr) * 1994-08-15 1996-02-22 Connaught Laboratories Limited Particules retroviriformes non infectieuses a marquage antigenique
WO1996006177A2 (fr) * 1994-08-22 1996-02-29 Connaught Laboratories Limited Particules semblables a des retrovirus rendues non-infectieuses par une pluralite de mutations
EP0745609A2 (fr) * 1995-06-01 1996-12-04 Frey, Rainer H. Vaccins pour la prophylaxie contre des infections par le virus VIH et/ou pour le traitement du SIDA et procédé de préparation
AU678152B2 (en) * 1992-03-27 1997-05-22 Whitehead Institute For Biomedical Research Non-infectious HIV particles and uses therefor
US5674720A (en) * 1988-11-10 1997-10-07 United States Of America Design and construction of non-infectious human retroviral mutants deficient in genomic RNA
US6013516A (en) * 1995-10-06 2000-01-11 The Salk Institute For Biological Studies Vector and method of use for nucleic acid delivery to non-dividing cells
US6121021A (en) * 1997-12-16 2000-09-19 Connaught Laboratories Limited Constitutive expression of non-infectious HIV-like particles
US6218181B1 (en) 1998-03-18 2001-04-17 The Salk Institute For Biological Studies Retroviral packaging cell line
US6291157B1 (en) 1998-02-23 2001-09-18 Connaught Laboratories Limited Antigenically-marked non-infectious retrovirus-like particles
US6518030B1 (en) 1994-08-15 2003-02-11 Aventis Pasteur Limited Antigentically-marked non-infectious retrovirus-like particles
EP1262554A3 (fr) * 1992-02-28 2007-08-29 Syngenix Limited Vecteurs non oncoviraux a encapsidation defectueuse bases sur le virus simiesque de mason-pfizer und hiv

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US5674720A (en) * 1988-11-10 1997-10-07 United States Of America Design and construction of non-infectious human retroviral mutants deficient in genomic RNA
EP0500791A4 (en) * 1989-10-31 1993-02-10 Us Health The design and construction of non-infectious human retroviral mutants deficient in genomic rna
EP0500791A1 (fr) * 1989-10-31 1992-09-02 THE UNITED STATES OF AMERICA as represented by the Secretary UNITED STATES DEPARTMENT OF COMMERCE Conception et construction des mutants retroviraux humains et non infectieux deficients dans l'arn genomique
EP0502105A1 (fr) * 1989-11-20 1992-09-09 Oncogen Limited Partnership Particules retrovirales non replicantes produites par recombinaton employees comme agents antiviraux et immunogenes
EP0502105A4 (en) * 1989-11-20 1993-02-24 Oncogen Limited Partnership Non-replicating recombinant-made retroviral particles used as antiviral agents and immunogens
WO1991019803A1 (fr) * 1990-06-19 1991-12-26 Applied Biotechnology, Incorporated Particules virales autoassemblees defectueuses qui ne se propagent pas d'elles-memes
WO1992022577A1 (fr) * 1991-06-17 1992-12-23 Neovacs Composes immunogenes a effet notamment anti-cytokine, procede de preparation, compositions pharmaceutiques et kits les renfermant
EP1262554A3 (fr) * 1992-02-28 2007-08-29 Syngenix Limited Vecteurs non oncoviraux a encapsidation defectueuse bases sur le virus simiesque de mason-pfizer und hiv
AU678152B2 (en) * 1992-03-27 1997-05-22 Whitehead Institute For Biomedical Research Non-infectious HIV particles and uses therefor
WO1996005292A1 (fr) * 1994-08-15 1996-02-22 Connaught Laboratories Limited Particules retroviriformes non infectieuses a marquage antigenique
US6518030B1 (en) 1994-08-15 2003-02-11 Aventis Pasteur Limited Antigentically-marked non-infectious retrovirus-like particles
US6025125A (en) * 1994-08-15 2000-02-15 Connaught Laboratories Limited Methods for the detection of HIV-specific immune responses employing non-infectious, non-replicating, IIV retrovirus-like particles containing heterologous antigenic markers
US6544752B1 (en) 1994-08-15 2003-04-08 Aventis Pasteur Limited Anigenically-marked non-infectious retrovirus-like particles
US5866320A (en) * 1994-08-15 1999-02-02 Connaught Laboratories Limited Nucleic acids encoding for non-infectious, replication-defective, self-assembling HIV-1 viral particles containing antigenic markers in the gag coding region
US5879925A (en) * 1994-08-15 1999-03-09 Connaught Laboratories Limited Genetically engineered human immunodeficiency virus-like particles with modified chimeric envelope glycoproteins containing influenza virus transmembrane spanning domains
US5889176A (en) * 1994-08-15 1999-03-30 Connaught Laboratories Limited Nucleic acid molecules encoding non-infectious, non-replicating, HIV retrovirus-like particles containing heterologous antigenic anchor sequences
US5955342A (en) * 1994-08-15 1999-09-21 Connaught Laboratories Limited Non-infectious, replication-defective, self-assembling HIV-1 viral particles containing antigenic markers in the gag coding region
US6342228B1 (en) 1994-08-15 2002-01-29 Aventis Pasteur Limited Diagnostic kits comprising genetically engineered human immunodeficiency virus-like particles containing heterologous antigenic markers
WO1996006177A3 (fr) * 1994-08-22 1996-07-25 Connaught Lab Particules semblables a des retrovirus rendues non-infectieuses par une pluralite de mutations
US6923970B2 (en) 1994-08-22 2005-08-02 Sanofi Pasteur Limited Retrovirus-like particles made non-infectious by a plurality of mutations
WO1996006177A2 (fr) * 1994-08-22 1996-02-29 Connaught Laboratories Limited Particules semblables a des retrovirus rendues non-infectieuses par une pluralite de mutations
US6080408A (en) * 1994-08-22 2000-06-27 Connaught Laboratories Limited Human immunodeficiency virus type 1 nucleic acids devoid of long terminal repeats capable of encoding for non-infectious, immunogenic, retrovirus-like particles
US6451322B1 (en) 1994-08-22 2002-09-17 Aventis Pasteur Limited Retrovirus like particles made non infectious by a plurality of mutations
US6544527B1 (en) 1994-08-22 2003-04-08 Aventis Pasteur Limited Non-infectious, immunogenic, human immunodeficiency virus-like particles devoid of long terminal repeats and a functional pol coding region
US7229625B2 (en) 1994-08-22 2007-06-12 Sanofi Pasteur Limited Retrovirus-like particles made non-infectious by a plurality of mutations
EP0745609A3 (fr) * 1995-06-01 1997-08-20 Frey Rainer H Vaccins pour la prophylaxie contre des infections par le virus VIH et/ou pour le traitement du SIDA et procédé de préparation
EP0745609A2 (fr) * 1995-06-01 1996-12-04 Frey, Rainer H. Vaccins pour la prophylaxie contre des infections par le virus VIH et/ou pour le traitement du SIDA et procédé de préparation
US6013516A (en) * 1995-10-06 2000-01-11 The Salk Institute For Biological Studies Vector and method of use for nucleic acid delivery to non-dividing cells
US6121021A (en) * 1997-12-16 2000-09-19 Connaught Laboratories Limited Constitutive expression of non-infectious HIV-like particles
US6291157B1 (en) 1998-02-23 2001-09-18 Connaught Laboratories Limited Antigenically-marked non-infectious retrovirus-like particles
US6727058B2 (en) 1998-03-18 2004-04-27 The Salk Institute For Biological Studies Intergrase assay
US6218181B1 (en) 1998-03-18 2001-04-17 The Salk Institute For Biological Studies Retroviral packaging cell line

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